How to shorten a barrel?

[RJW NZ]

Is there any consensus about where to make the cut? I have a vague memory/idea that cutting in the wrong place could make a more inaccurate rifle, something to do with harmonics etc.

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[xa-coupe]

I would guess just after one of the pressure points would be the spot, depending on how short they want.

[jmoore]

If it's been sporterized, which I reckon would have to be the case, then there's not much way to tell if you'll stray far from a vibration node. It's not fixed! when you shorten it, the harmonics naturally change. But shortening adds greatly to the rigidity of a cantilevered structure. IIRC, the length variable in deflection is "X to the fourth power", so, if you double the length it's gonna be sixteen times less rigid! (That only works exactly on a structure of uniform cross section- a tapered structure will be even more rigid.) So, little changes can help!

[browningautorifle]

Most of the guys that want a truck gun can't hit a bull in the a** with a shovel. If the rifle (18"bbl) will do 4" at 100 then that should be good. They did anyway. There wasn't much difference. These aren't match rifles we're building...

[Claven2]

I rather suspect that the location of the cut will have negligible effect on accuracy with a milsurp barrel. If it were a bedded and cryo-treated air-gauged match barrel, maybe... but it's not.